Table 1.
Study demographics, matching variables and quality assessment.
| Study | Country | Study design | Study center | Study year | Surgical treatment | Matching variables# | Follow-up time (months) (median [range]) | Quality assessment (stars allocated) | ||
|---|---|---|---|---|---|---|---|---|---|---|
| Selection | Comparability | Outcome | ||||||||
| Bilani et al. (24) | America | Retrospective unmatched | Multicenter | 2010-2016 | LR | – | – | 4 | 0 | 1 |
| Chun et al. (23) | America | Retrospective matched | Single center | 1997-2016 | LR | d, f, g, h, i, j, k, l, q, s, t, x | 57 (9-229) in LR+ST cohort, 18 (0-213) in ST cohort | 4 | 2 | 2 |
| Feng et al. (22) | China | Retrospective matched | Single center | 2008-2018 | LR | Not specific | 47.0 (1.5-89.0) in LR+ST cohort, 53.7 (0.1-139.7) in ST cohort | 4 | 2 | 3 |
| Mariani et al. (28) | France | Retrospective matched | Single center | 1988-2007 | LR | a, c, e, f, h, i, j | – | 4 | 1 | 1 |
| Millen et al. (21) | America | Retrospective unmatched | Multicenter | 2010-2014 | LR | – | – | 4 | 0 | 1 |
| Ruiz et al. (25) | France and Netherlands | Retrospective matched | Multicenter | 1985-2013 | LR | b, d, e, r, s, u, v, w | 80 in whole cohort, 69 in LR+ST cohort, 80 in ST cohort | 3 | 2 | 3 |
| Sadot et al. (26) | America | Retrospective matched | Single center | 1991-2014 | LR/RFA | e, i, m, n, o, p, q | 73 in whole cohort, 89 in LR/RFA+ST cohort, 62 in ST cohort | 4 | 2 | 3 |
| Sunden 2020 | Sweden | Retrospective unmatched | Multicenter | 2009-2016 | LR/RFA | – | – | 4 | 1 | 2 |
| Tasci 2013 | America | Prospective matched | Single center | 1996-2011 | RFA | e, q, s | 20 (6–101) in RFA+ST cohort, 27 in ST cohort | 4 | 2 | 2 |
Matching variables: Demographics and time interval: a) age at diagnosis of breast cancer, b) age at diagnosis of liver metastases, c) year of breast cancer diagnosis, d) year of liver metastases diagnosis, e) time between breast cancer diagnosis and first liver metastasis. Primary breast tumor: f) TNM stage, g) tumor grade, h) histology, i) ER status, j) PR status, k) HER2 status, l) resection of primary tumor, m) type of breast surgery, n) adjuvant chemotherapy after breast surgery, o) adjuvant radiotherapy after breast surgery, p) targeted therapy. Breast cancer liver metastases: q) number of liver metastases, r) single or multiple metastasis, s) size of liver metastases, t) synchronous liver metastases, u) chemotherapy after diagnosis of liver metastases, v) hormonal therapy after diagnosis of liver metastases, w) targeted therapy after diagnosis of liver metastases, x) best RECIST response to first-line systemic therapy. LR, liver resection; ST, systemic treatment; RFA, radiofrequency ablation.